1. Field of the Invention
The present invention relates to an apparatus for removing mold and other detritus from raisins and the like, and more particularly to such an apparatus for use by packers in processing raisins which have become moldy in the vineyard due to rainfall during the normal period of solar drying.
2. Description of the Prior Art
Dried fruits, such as raisins and the like, are usually prepared by exposing them in the field to solar radiation for a period of time. This method of preparation is, of course, only practical in regions where rain does not normally fall in significant quantities during the drying period. When rain does fall during the drying period, the result is often economic disaster for the entire raisin industry. The principal harm resulting from unseasonable rainfall is that mold and decay attack the raisins because of dampness following the rain and because of the protracted drying period required. For example, as a result of unseasonable rainfall in the San Joaquin Valley of California in the fall of 1978, of 94,000 tons of raisins delivered to packers, approximately 77,800 tons were unmarketable because of mold damage. Many thousands of tons were not even delivered because of such damage.
It is well known to attempt to salvage moldy raisins by washing them with hot water. However, mold which forms on raisins which have become damp during the drying period is so closely adherent that it is not sufficiently removed by washing with water. Therefore, it has been attempted to remove the mold by abrasion. However, the mold is so adherent that prior art methods and apparatus which apply sufficient abrasion to remove the mold frequently remove portions of the skin together with the mold. The resulting raisins are not acceptable since their sticky interiors thus exposed cause the raisins to stick together as well as permitting the entry of decay causing organisms.